/Engine/Plugins/Experimental/TextToSpeech/Source/TextToSpeech/Public/TextToSpeechEngineSubsystem.h
Removes all text to speech channels, preventin future requests for text to speech functionality on all channels.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=TextToSpeech) void RemoveAllChannels()